Manufacture of solder-cored wire.



F. mwnxmum. MANUFACTURE OF SOLDER GORE-D WIRE.

APPLICATION FILED FEB. 27,1911.

Patented Sept. 1, 1914.?

FRIEDRICH KAMMERER, OF BFORZHEIM, GERMANY.

MANUFACTURE OF SOLDER-CORED WIRE.

Specification of Letters Patent.

Patented Sept. 1, 1914:.

Application filed February 27, 1911. Serial No. 611.168.

To all whom it may concern Be it known that I, FRIEDRICH Kam- MERER, a citizen of Baden, residing at Pforzheim, in Germany, have invented a certain new and useful Improvement in the Mannfacture of Solder-Cored ire, of which the following is a specification.

This invention relates to wire for use in the manufacture of jewelry and the like, provided with an annular core of solder placed around a tough central core to enable joints to be made by melting the solder while ends of the wire are held together. In using wire of this kind certain disadvantages have been found to arise from lack of a firm connection between the solder and the tough central core. The solder is liable to be torn and become detached, frequently renderin the wire useless for the purpose indicate The object of the present invention is to remove this disadvantage, and the invention substantially consists in uniting the layer of solder to the internal tough core by melting, so as to make a firm jointbetween them.

The invention is illustrated in the accom panying drawing, in which Figure 1 is side-view of a piece of the wire, much enlarged, and partly in section, Fig. 2 being a cross-section thereof. Fig. 3 is a cross section, showingthe preferred construction.

Referring in the first place to Figs. 1 and 2, a is the outer layer or sheath, which may be of gold or sliver or consist of a base metal with a superficial layer of gold or silver, I) the tough inner core, and c the annular layer of solder between same, the solder a being united to thecore b, by melting as already stated. The core is tougher and more ductile than the outer layer and the solder, and may, for exan'lple, consist of tombac, which is a kind of brass formed of an alloy of copper, zinc and tin. The melting of the solder may be effected by passing the core I) with the solder layer thereon through gasflames forcibly blown thereon, the wire being continuously rotated and axially moved. so that the solder melts on the surface of the core and firmly unites therewith.

In the form shown in Fig. 3 a layer of tomb'ac or the like (i is placed around the solder 0, between the latter and the jacket a This shell (Z? protects the solder from touch by hand, during insertion into the sheath or other manipulation, and also facilitates the operation of uniting the core and solder by melting, enabling the same to be performed, by heating, after insertion into the sheath. By this heating the solder is melted and united to the core 72 and shell The shell (P does not form a neutral zone between the sheath and solder.

The breaking and tearing out of the solder is rendered practically impossible by the adherence of the solder to the inner core and to the layer of the same material (when such is used) produced by the method of melting the solder as above described.

\Vhat I claim as my invention and desire to secure by Letters Patent of the United State is:-

1. Composite wire for the purpose set forth comprising a core, a massive layer of solder surrounding said core and united therew'ith'by melting, and an external metal sheath.

2. Composite wire for the purpose set forth comprising a .metal sheath, a central core. a massive layer of solder surrounding said core and united therewith by melting, and a layer of metal tougher than said sheath between the latter and said massive layer of solder.

3. The method ofproducing composite wire which consistsin forming a core, surrounding said core with a masslve layer of solder, uniting said solder layer with said core by'melting, inserting said core and solder layer into a metal sheath, and reducing the ingot thus-prepared to wire.

In. witness whereof I have signed this specification in the presence of two Witnesses.

FRIEDRICH KAMMERER.

\Vitnesses:

A. O. TIT'IMANN, S. H. SHANK. 

